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Lundgren JG, Flynn MG, List K. GPI-anchored serine proteases: essential roles in development, homeostasis, and disease. Biol Chem 2025; 406:1-28. [PMID: 40094301 DOI: 10.1515/hsz-2024-0135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2024] [Accepted: 02/23/2025] [Indexed: 03/19/2025]
Abstract
The glycosylphosphatidylinositol (GPI)-anchored serine proteases, prostasin and testisin, have essential roles in diverse physiological functions including development, reproduction, homeostasis and barrier function of epithelia, angiogenesis, coagulation, and fibrinolysis. Important functions in pathological conditions such as cancer, kidney disease and cardiovascular disease have also been reported. In this review, we summarize current knowledge of the cellular and in vivo roles of prostasin and testisin in physiology and pathophysiology and explore the underlying molecular mechanisms. We discuss how new insights of their role in cancer and cardiovascular disease may facilitate translation into clinical settings in the future.
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Affiliation(s)
- Joseph G Lundgren
- Department of Pharmacology, Wayne State University, Detroit, MI 48201, USA
- Department of Oncology, Wayne State University, Detroit, MI 48201, USA
| | - Michael G Flynn
- Department of Pharmacology, Wayne State University, Detroit, MI 48201, USA
| | - Karin List
- Department of Pharmacology, Wayne State University, Detroit, MI 48201, USA
- Department of Oncology, Wayne State University, Detroit, MI 48201, USA
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2
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Chen Y, Liu S, Gong W, Guo P, Xue F, Zhou X, Wang S, Yuan Z. Protein-centric omics integration analysis identifies candidate plasma proteins for multiple autoimmune diseases. Hum Genet 2024; 143:1035-1048. [PMID: 38143258 PMCID: PMC11485194 DOI: 10.1007/s00439-023-02627-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 11/28/2023] [Indexed: 12/26/2023]
Abstract
It remains challenging to translate the findings from genome-wide association studies (GWAS) of autoimmune diseases (AIDs) into interventional targets, presumably due to the lack of knowledge on how the GWAS risk variants contribute to AIDs. In addition, current immunomodulatory drugs for AIDs are broad in action rather than disease-specific. We performed a comprehensive protein-centric omics integration analysis to identify AIDs-associated plasma proteins through integrating protein quantitative trait loci datasets of plasma protein (1348 proteins and 7213 individuals) and totally ten large-scale GWAS summary statistics of AIDs under a cutting-edge systematic analytic framework. Specifically, we initially screened out the protein-AID associations using proteome-wide association study (PWAS), followed by enrichment analysis to reveal the underlying biological processes and pathways. Then, we performed both Mendelian randomization (MR) and colocalization analyses to further identify protein-AID pairs with putatively causal relationships. We finally prioritized the potential drug targets for AIDs. A total of 174 protein-AID associations were identified by PWAS. AIDs-associated plasma proteins were significantly enriched in immune-related biological process and pathways, such as inflammatory response (P = 3.96 × 10-10). MR analysis further identified 97 protein-AID pairs with potential causal relationships, among which 21 pairs were highly supported by colocalization analysis (PP.H4 > 0.75), 10 of 21 were the newly discovered pairs and not reported in previous GWAS analyses. Further explorations showed that four proteins (TLR3, FCGR2A, IL23R, TCN1) have corresponding drugs, and 17 proteins have druggability. These findings will help us to further understand the biological mechanism of AIDs and highlight the potential of these proteins to develop as therapeutic targets for AIDs.
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Affiliation(s)
- Yingxuan Chen
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Shuai Liu
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Weiming Gong
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Ping Guo
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Fuzhong Xue
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Xiang Zhou
- Department of Biostatistics, University of Michigan, Ann Arbor, MI, 48109, USA
- Center for Statistical Genetics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Shukang Wang
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China.
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China.
| | - Zhongshang Yuan
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China.
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China.
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3
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Huang N, Wang Q, Bernard RB, Chen CY, Hu JM, Wang JK, Chan KS, Johnson MD, Lin CY. SPINT2 mutations in the Kunitz domain 2 found in SCSD patients inactivate HAI-2 as prostasin inhibitor via abnormal protein folding and N-glycosylation. Hum Mol Genet 2024; 33:752-767. [PMID: 38271183 PMCID: PMC11031362 DOI: 10.1093/hmg/ddae005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 11/30/2023] [Accepted: 01/05/2024] [Indexed: 01/27/2024] Open
Abstract
Mutations in the Kunitz-type serine protease inhibitor HAI-2, encoded by SPINT2, are responsible for the pathogenesis of syndromic congenital sodium diarrhea (SCSD), an intractable secretory diarrhea of infancy. Some of the mutations cause defects in the functionally required Kunitz domain 1 and/or subcellular targeting signals. Almost all SCSD patients, however, harbor SPINT2 missense mutations that affect the functionally less important Kunitz domain 2. How theses single amino acid substitutions inactivate HAI-2 was, here, investigated by the doxycycline-inducible expression of three of these mutants in HAI-2-knockout Caco-2 human colorectal adenocarcinoma cells. Examining protein expressed from these HAI-2 mutants reveals that roughly 50% of the protein is synthesized as disulfide-linked oligomers that lose protease inhibitory activity due to the distortion of the Kunitz domains by disarrayed disulfide bonding. Although the remaining protein is synthesized as monomers, its glycosylation status suggests that the HAI-2 monomer remains in the immature, lightly glycosylated form, and is not converted to the heavily glycosylated mature form. Heavily glycosylated HAI-2 possesses full anti-protease activity and appropriate subcellular targeting signals, including the one embedded in the complex-type N-glycan. As predicted, these HAI-2 mutants cannot suppress the excessive prostasin proteolysis caused by HAI-2 deletion. The oligomerization and glycosylation defects have also been observed in a colorectal adenocarcinoma line that harbors one of these SPINT2 missense mutations. Our study reveals that the abnormal protein folding and N-glycosylation can cause widespread HAI-2 inactivation in SCSD patents.
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Affiliation(s)
- Nanxi Huang
- Lombardi Comprehensive Cancer Center, Department of Oncology, Georgetown University, 3970 Reservoir Road NW W422 New Research Building, Washington DC 20057, United States
| | - Qiaochu Wang
- Lombardi Comprehensive Cancer Center, Department of Oncology, Georgetown University, 3970 Reservoir Road NW W422 New Research Building, Washington DC 20057, United States
| | - Robert B Bernard
- Lombardi Comprehensive Cancer Center, Department of Oncology, Georgetown University, 3970 Reservoir Road NW W422 New Research Building, Washington DC 20057, United States
| | - Chao-Yang Chen
- School of Medicine, National Defense Medical Center, No. 161, sec. 6, Minquan E. Road, Neihu Dist. Taipei City 11490, Taiwan, ROC
- Division of Colorectal Surgery, Department of Surgery, Tri-Service General Hospital, No. 325, Sec. 2, Chenggon Road, Neihu Dist. Taipei City 114202, Taiwan, ROC
| | - Je-Ming Hu
- School of Medicine, National Defense Medical Center, No. 161, sec. 6, Minquan E. Road, Neihu Dist. Taipei City 11490, Taiwan, ROC
- Division of Colorectal Surgery, Department of Surgery, Tri-Service General Hospital, No. 325, Sec. 2, Chenggon Road, Neihu Dist. Taipei City 114202, Taiwan, ROC
- Graduate Institute of Medical Sciences, National Defense Medical Center, No. 161, sec. 6, Minquan E. Neihu Dist. Taipei City 11490, Taiwan, ROC
| | - Jehng-Kang Wang
- Department of Biochemistry, National Defense Medical Center, No. 161, sec. 6, Minquan E. Road, Taipei City, 11490, Taiwan, ROC
| | - Khee-Siang Chan
- Department of Intensive Care Medicine, Chi Mei Medical Center, No. 901, Zhonghua Road, Yongkang Dist., Tainan City, 71004, Taiwan, ROC
| | - Michael D Johnson
- Lombardi Comprehensive Cancer Center, Department of Oncology, Georgetown University, 3970 Reservoir Road NW W422 New Research Building, Washington DC 20057, United States
| | - Chen-Yong Lin
- Lombardi Comprehensive Cancer Center, Department of Oncology, Georgetown University, 3970 Reservoir Road NW W422 New Research Building, Washington DC 20057, United States
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4
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Liu C, Guo G, Li X, Shen Y, Xu X, Chen Y, Li H, Hao J, He K. Identification of novel urine proteomic biomarkers for high stamina in high-altitude adaptation. Front Physiol 2023; 14:1153166. [PMID: 37250129 PMCID: PMC10214468 DOI: 10.3389/fphys.2023.1153166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Accepted: 04/21/2023] [Indexed: 05/31/2023] Open
Abstract
Introduction: We aimed to identify urine biomarkers for screening individuals with adaptability to high-altitude hypoxia with high stamina levels. Although most non-high-altitude natives experience rapid decline in physical ability when ascending to high altitudes, some individuals with high-altitude adaptability continue to maintain high endurance levels. Methods: We divided the study population into two groups: the LC group (low change in endurance from low to high altitude) and HC group (high change in endurance from low to high altitude). We performed blood biochemistry testing for individuals at high altitudes and sea level. We used urine peptidome profiling to compare the HH (high-altitude with high stamina) and HL (high-altitude with low stamina) groups and the LC and HC groups to identify urine biomarkers. Results: Routine blood tests revealed that the concentration of white blood cells, lymphocytes and platelets were significantly higher in the HH group than in the HL group. Urine peptidome profiling showed that the proteins ITIH1, PDCD1LG2, NME1-NME2, and CSPG4 were significantly differentially expressed between the HH and HL groups, which was tested using ELISA. Urine proteomic analysis showed that LRG1, NID1, VASN, GPX3, ACP2, and PRSS8 were urine proteomic biomarkers of high stamina during high-altitude adaptation. Conclusion: This study provides a novel approach for identifying potential biomarkers for screening individuals who can adapt to high altitudes with high stamina.
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Affiliation(s)
- Chunlei Liu
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, China
| | - Ge Guo
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, China
| | - Xin Li
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, China
| | - Yanying Shen
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, China
| | - Xiang Xu
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, China
| | - Yibing Chen
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, China
| | - Hanlu Li
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, China
| | - Jianxiu Hao
- Clinical Sample Bank, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, China
| | - Kunlun He
- Medical Big Data Research Center, Chinese PLA General Hospital, Beijing, China
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5
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Huang N, Wang Q, Chen CY, Hu JM, Wang JK, Chang PY, Johnson MD, Lin CY. N-glycosylation on Asn-57 is required for the correct HAI-2 protein folding and protease inhibitory activity. Glycobiology 2023; 33:203-214. [PMID: 36637420 PMCID: PMC10114645 DOI: 10.1093/glycob/cwad002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 12/13/2022] [Accepted: 01/02/2023] [Indexed: 01/14/2023] Open
Abstract
Hepatocyte growth factor activator inhibitor (HAI)-2 is an integral membrane Kunitz-type serine protease inhibitor that regulates the proteolysis of matriptase and prostasin in a cell-type selective manner. The cell-type selective nature of HAI-2 function depends largely on whether the inhibitor and potential target enzymes are targeted to locations in close proximity. The N-glycan moiety of HAI-2 can function as a subcellular targeting signal. HAI-2 is synthesized with 1 of 2 different N-glycan modifications: one of oligomannose-type, which largely remains in the endoplasmic reticulum/GA, and another of complex-type, which is targeted toward the apical surface in vesicle-like structures, and could function as an inhibitor of matriptase and prostasin. HAI-2 contains 2 putative N-glycosylation sites, Asn-57 and Asn-94, point mutations of which were generated and characterized in this study. The protein expression profile of the HAI-2 mutants indicates that Asn-57, and not Asn-94, is responsible for the N-glycosylation of both HAI-2 species, suggesting that the form with oligomannose-type N-glycan is the precursor of the form with complex-type N-glycan. Unexpectedly, the vast majority of non-glycosylated HAI-2 is synthesized into multiple disulfide-linked oligomers, which lack protease inhibitory function, likely due to distorted conformations caused by the disarrayed disulfide linkages. Although forced expression of HAI-2 in HAI-2 knockout cells artificially enhances HAI-2 oligomerization, disulfide-linked HAI-2 oligomers can also be observed in unmodified cells. These results suggest that N-glycosylation on Asn-57 is required for folding into a functional HAI-2 with full protease suppressive activity and correct subcellular targeting signal.
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Affiliation(s)
- Nanxi Huang
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, United States
| | - Qiaochu Wang
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, United States
| | - Chao-Yang Chen
- School of Medicine, National Defense Medical Center, Taipei 114, Taiwan, ROC
- Division of Colorectal Surgery, Department of Surgery, Tri-Service General Hospital, Taipei 114, Taiwan, ROC
| | - Je-Ming Hu
- School of Medicine, National Defense Medical Center, Taipei 114, Taiwan, ROC
- Division of Colorectal Surgery, Department of Surgery, Tri-Service General Hospital, Taipei 114, Taiwan, ROC
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei 114, Taiwan, ROC
| | - Jehng-Kang Wang
- Department of Biochemistry, National Defense Medical Center, Taipei 114, Taiwan, ROC
| | - Ping-Ying Chang
- School of Medicine, National Defense Medical Center, Taipei 114, Taiwan, ROC
- Division of Hematology/Oncology, Department of internal medicine, Tri-Service General Hospital, Taipei 114, Taiwan, ROC
| | - Michael D Johnson
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, United States
| | - Chen-Yong Lin
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, United States
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6
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Wall SM. Regulation of Blood Pressure and Salt Balance By Pendrin-Positive Intercalated Cells: Donald Seldin Lecture 2020. Hypertension 2022; 79:706-716. [PMID: 35109661 PMCID: PMC8918038 DOI: 10.1161/hypertensionaha.121.16492] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Intercalated cells make up about a third of all cells within the connecting tubule and the collecting duct and are subclassified as type A, type B and non-A, non-B based on the subcellular distribution of the H+-ATPase, which dictates whether it secretes H+ or HCO3-. Type B intercalated cells mediate Cl- absorption and HCO3- secretion, which occurs largely through the anion exchanger pendrin. Pendrin is stimulated by angiotensin II via the angiotensin type 1a receptor and by aldosterone through MR (mineralocorticoid receptor). Aldosterone stimulates pendrin expression and function, in part, through the alkalosis it generates. Pendrin-mediated HCO3- secretion increases in models of metabolic alkalosis, which attenuates the alkalosis. However, pendrin-positive intercalated cells also regulate blood pressure, at least partly, through pendrin-mediated Cl- absorption and through their indirect effect on the epithelial Na+ channel, ENaC. This aldosterone-induced increase in pendrin secondarily stimulates ENaC, thereby contributing to the aldosterone pressor response. This review describes the contribution of pendrin-positive intercalated cells to Na+, K+, Cl- and acid-base balance.
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Affiliation(s)
- Susan M. Wall
- Department of Medicine, Emory University School of Medicine, Atlanta, GA
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7
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Wang XP, Balchak DM, Gentilcore C, Clark NL, Kashlan OB. Activation by cleavage of the epithelial Na + channel α and γ subunits independently coevolved with the vertebrate terrestrial migration. eLife 2022; 11:75796. [PMID: 34984981 PMCID: PMC8791634 DOI: 10.7554/elife.75796] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 12/28/2021] [Indexed: 12/17/2022] Open
Abstract
Vertebrates evolved mechanisms for sodium conservation and gas exchange in conjunction with migration from aquatic to terrestrial habitats. Epithelial Na+ channel (ENaC) function is critical to systems responsible for extracellular fluid homeostasis and gas exchange. ENaC is activated by cleavage at multiple specific extracellular polybasic sites, releasing inhibitory tracts from the channel’s α and γ subunits. We found that proximal and distal polybasic tracts in ENaC subunits coevolved, consistent with the dual cleavage requirement for activation observed in mammals. Polybasic tract pairs evolved with the terrestrial migration and the appearance of lungs, coincident with the ENaC activator aldosterone, and appeared independently in the α and γ subunits. In summary, sites within ENaC for protease activation developed in vertebrates when renal Na+ conservation and alveolar gas exchange were required for terrestrial survival.
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Affiliation(s)
- Xue-Ping Wang
- Department of Medicine, University of Pittsburgh, Pittsburgh, United States
| | - Deidra M Balchak
- Department of Medicine, University of Pittsburgh, Pittsburgh, United States
| | - Clayton Gentilcore
- Department of Medicine, University of Pittsburgh, Pittsburgh, United States
| | - Nathan L Clark
- Department of Human Genetics, University of Utah, Salt Lake City, United States
| | - Ossama B Kashlan
- Department of Medicine, University of Pittsburgh, Pittsburgh, United States.,Computational and Systems Biology, University of Pittsburgh, Pittsburgh, United States
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8
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Barndt RB, Lee MJ, Huang N, Lu DD, Lee SC, Du PW, Chang CC, Tsai PFB, Huang YSK, Chang HM, Wang JK, Lai CH, Johnson MD, Lin CY. Targeted HAI-2 deletion causes excessive proteolysis with prolonged active prostasin and depletion of HAI-1 monomer in intestinal but not epidermal epithelial cells. Hum Mol Genet 2021; 30:1833-1850. [PMID: 34089062 PMCID: PMC8444455 DOI: 10.1093/hmg/ddab150] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 11/12/2022] Open
Abstract
Mutations of SPINT2, the gene encoding the integral membrane, Kunitz-type serine inhibitor HAI-2, primarily affect the intestine, while sparing many other HAI-2-expressing tissues, causing sodium loss in patients with syndromic congenital sodium diarrhea. The membrane-bound serine protease prostasin was previously identified as a HAI-2 target protease in intestinal tissues but not in the skin. In both tissues, the highly related inhibitor HAI-1 is, however, the default inhibitor for prostasin and the type 2 transmembrane serine protease matriptase. This cell-type selective functional linkage may contribute to the organ-selective damage associated with SPINT 2 mutations. To this end, the impact of HAI-2 deletion on matriptase and prostasin proteolysis was, here, compared using Caco-2 human colorectal adenocarcinoma cells and HaCaT human keratinocytes. Greatly enhanced prostasin proteolytic activity with a prolonged half-life and significant depletion of HAI-1 monomer were observed with HAI-2 loss in Caco-2 cells but not HaCaT cells. The constitutive, high level prostasin zymogen activation observed in Caco-2 cells, but not in HaCaT cells, also contributes to the excessive prostasin proteolytic activity caused by HAI-2 loss. HAI-2 deletion also caused increased matriptase zymogen activation, likely as an indirect result of increased prostasin proteolysis. This increase in activated matriptase, however, only had a negligible role in depletion of HAI-1 monomer. Our study suggests that the constitutive, high level of prostasin zymogen activation and the cell-type selective functional relationship between HAI-2 and prostasin renders Caco-2 cells more susceptible than HaCaT cells to the loss of HAI-2, causing a severe imbalance favoring prostasin proteolysis.
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Affiliation(s)
- Robert B Barndt
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University, Washington, DC 20057, USA
| | - Mon-Juan Lee
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University, Washington, DC 20057, USA
- Department of Bioscience Technology, Chang Jung Christian University, Tainan 71101, Taiwan
- Department of Medical Science Industries, Chang Jung Christian University, Tainan 71101, Taiwan
| | - Nanxi Huang
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University, Washington, DC 20057, USA
| | - Dajun D Lu
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University, Washington, DC 20057, USA
| | - See-Chi Lee
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University, Washington, DC 20057, USA
| | - Po-Wen Du
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University, Washington, DC 20057, USA
- Department of Biochemistry National Defense Medical Center, Taipei 114, Taiwan
| | - Chun-Chia Chang
- School of Medicine, National Defense Medical Center, Taipei 114, Taiwan
| | - Ping-Feng B Tsai
- School of Medicine, National Defense Medical Center, Taipei 114, Taiwan
| | - Yu-Siou K Huang
- School of Medicine, National Defense Medical Center, Taipei 114, Taiwan
| | - Hao-Ming Chang
- Department of Surgery, Tri-Service General Hospital, Taipei 114, Taiwan
| | - Jehng-Kang Wang
- Department of Biochemistry National Defense Medical Center, Taipei 114, Taiwan
| | - Chih-Hsin Lai
- Department of Dentistry Renai Branch, Taipei City Hospital, Taipei 106, Taiwan
| | - Michael D Johnson
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University, Washington, DC 20057, USA
| | - Chen-Yong Lin
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University, Washington, DC 20057, USA
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9
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Sekine T, Takizawa S, Uchimura K, Miyazaki A, Tsuchiya K. Liver-Specific Overexpression of Prostasin Attenuates High-Fat Diet-Induced Metabolic Dysregulation in Mice. Int J Mol Sci 2021; 22:ijms22158314. [PMID: 34361079 PMCID: PMC8348244 DOI: 10.3390/ijms22158314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/12/2021] [Accepted: 07/30/2021] [Indexed: 01/20/2023] Open
Abstract
The liver has a most indispensable role in glucose and lipid metabolism where we see some of the most serious worldwide health problems. The serine protease prostasin (PRSS8) cleaves toll-like receptor 4 (TLR4) and regulates hepatic insulin sensitivity under PRSS8 knockout condition. However, liver substrate proteins of PRSS8 other than TLR4 and the effect to glucose and lipid metabolism remain unclarified with hepatic elevation of PRSS8 expression. Here we show that high-fat-diet-fed liver-specific PRSS8 transgenic mice improved glucose tolerance and hepatic steatosis independent of body weight. PRSS8 amplified extracellular signal-regulated kinase phosphorylation associated with matrix metalloproteinase 14 activation in vivo and in vitro. Moreover, in humans, serum PRSS8 levels reduced more in type 2 diabetes mellitus (T2DM) patients than healthy controls and were lower in T2DM patients with increased maximum carotid artery intima media thickness (>1.1 mm). These results identify the regulatory mechanisms of PRSS8 overexpression over glucose and lipid metabolism, as well as excessive hepatic fat storage.
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Affiliation(s)
- Tetsuo Sekine
- Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo 4093898, Japan; (T.S.); (S.T.); (K.U.)
| | - Soichi Takizawa
- Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo 4093898, Japan; (T.S.); (S.T.); (K.U.)
- Internal Medicine, Yamanashi Prefectural Central Hospital, Kofu 4008506, Japan
| | - Kohei Uchimura
- Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo 4093898, Japan; (T.S.); (S.T.); (K.U.)
| | | | - Kyoichiro Tsuchiya
- Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo 4093898, Japan; (T.S.); (S.T.); (K.U.)
- Correspondence: ; Tel.: +81-55-273-9682
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10
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Carroll EL, Bailo M, Reihill JA, Crilly A, Lockhart JC, Litherland GJ, Lundy FT, McGarvey LP, Hollywood MA, Martin SL. Trypsin-Like Proteases and Their Role in Muco-Obstructive Lung Diseases. Int J Mol Sci 2021; 22:5817. [PMID: 34072295 PMCID: PMC8199346 DOI: 10.3390/ijms22115817] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 12/20/2022] Open
Abstract
Trypsin-like proteases (TLPs) belong to a family of serine enzymes with primary substrate specificities for the basic residues, lysine and arginine, in the P1 position. Whilst initially perceived as soluble enzymes that are extracellularly secreted, a number of novel TLPs that are anchored in the cell membrane have since been discovered. Muco-obstructive lung diseases (MucOLDs) are characterised by the accumulation of hyper-concentrated mucus in the small airways, leading to persistent inflammation, infection and dysregulated protease activity. Although neutrophilic serine proteases, particularly neutrophil elastase, have been implicated in the propagation of inflammation and local tissue destruction, it is likely that the serine TLPs also contribute to various disease-relevant processes given the roles that a number of these enzymes play in the activation of both the epithelial sodium channel (ENaC) and protease-activated receptor 2 (PAR2). More recently, significant attention has focused on the activation of viruses such as SARS-CoV-2 by host TLPs. The purpose of this review was to highlight key TLPs linked to the activation of ENaC and PAR2 and their association with airway dehydration and inflammatory signalling pathways, respectively. The role of TLPs in viral infectivity will also be discussed in the context of the inhibition of TLP activities and the potential of these proteases as therapeutic targets.
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Affiliation(s)
- Emma L. Carroll
- School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK; (E.L.C.); (J.A.R.)
| | - Mariarca Bailo
- Institute for Biomedical and Environmental Health Research, School of Health and Life Sciences, University of the West of Scotland, Paisley PA1 2BE, UK; (M.B.); (A.C.); (J.C.L.); (G.J.L.)
| | - James A. Reihill
- School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK; (E.L.C.); (J.A.R.)
| | - Anne Crilly
- Institute for Biomedical and Environmental Health Research, School of Health and Life Sciences, University of the West of Scotland, Paisley PA1 2BE, UK; (M.B.); (A.C.); (J.C.L.); (G.J.L.)
| | - John C. Lockhart
- Institute for Biomedical and Environmental Health Research, School of Health and Life Sciences, University of the West of Scotland, Paisley PA1 2BE, UK; (M.B.); (A.C.); (J.C.L.); (G.J.L.)
| | - Gary J. Litherland
- Institute for Biomedical and Environmental Health Research, School of Health and Life Sciences, University of the West of Scotland, Paisley PA1 2BE, UK; (M.B.); (A.C.); (J.C.L.); (G.J.L.)
| | - Fionnuala T. Lundy
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University, Belfast BT9 7BL, UK; (F.T.L.); (L.P.M.)
| | - Lorcan P. McGarvey
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University, Belfast BT9 7BL, UK; (F.T.L.); (L.P.M.)
| | - Mark A. Hollywood
- Smooth Muscle Research Centre, Dundalk Institute of Technology, A91 HRK2 Dundalk, Ireland;
| | - S. Lorraine Martin
- School of Pharmacy, Queen’s University, Belfast BT9 7BL, UK; (E.L.C.); (J.A.R.)
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11
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Essigke D, Ilyaskin AV, Wörn M, Bohnert BN, Xiao M, Daniel C, Amann K, Birkenfeld AL, Szabo R, Bugge TH, Korbmacher C, Artunc F. Zymogen-locked mutant prostasin (Prss8) leads to incomplete proteolytic activation of the epithelial sodium channel (ENaC) and severely compromises triamterene tolerance in mice. Acta Physiol (Oxf) 2021; 232:e13640. [PMID: 33650216 DOI: 10.1111/apha.13640] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 02/15/2021] [Accepted: 02/26/2021] [Indexed: 02/06/2023]
Abstract
AIM The serine protease prostasin (Prss8) is expressed in the distal tubule and stimulates proteolytic activation of the epithelial sodium channel (ENaC) in co-expression experiments in vitro. The aim of this study was to explore the role of prostasin in proteolytic ENaC activation in the kidney in vivo. METHODS We used genetically modified knockin mice carrying a Prss8 mutation abolishing proteolytic activity (Prss8-S238A) or a mutation leading to a zymogen-locked state (Prss8-R44Q). Mice were challenged with low sodium diet and diuretics. Regulation of ENaC activity by Prss8-S238A and Prss8-R44Q was studied in vitro using the Xenopus laevis oocyte expression system. RESULTS Co-expression of murine ENaC with Prss8-wt or Prss8-S238A in oocytes caused maximal proteolytic ENaC activation, whereas ENaC was activated only partially in oocytes co-expressing Prss8-R44Q. This was paralleled by a reduced proteolytic activity at the cell surface of Prss8-R44Q expressing oocytes. Sodium conservation under low sodium diet was preserved in Prss8-S238A and Prss8-R44Q mice but with higher plasma aldosterone concentrations in Prss8-R44Q mice. Treatment with the ENaC inhibitor triamterene over four days was tolerated in Prss8-wt and Prss8-S238A mice, whereas Prss8-R44Q mice developed salt wasting and severe weight loss associated with hyperkalemia and acidosis consistent with impaired ENaC function and renal failure. CONCLUSION Unlike proteolytically inactive Prss8-S238A, zymogen-locked Prss8-R44Q produces incomplete proteolytic ENaC activation in vitro and causes a severe renal phenotype in mice treated with the ENaC inhibitor triamterene. This indicates that Prss8 plays a role in proteolytic ENaC activation and renal function independent of its proteolytic activity.
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Affiliation(s)
- Daniel Essigke
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tuebingen Germany
| | - Alexandr V. Ilyaskin
- Institute of Cellular and Molecular Physiology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Matthias Wörn
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tuebingen Germany
| | - Bernhard N. Bohnert
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tuebingen Germany
- Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University Tübingen Tuebingen Germany
- German Center for Diabetes Research (DZD) at the University Tübingen Tuebingen Germany
| | - Mengyun Xiao
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tuebingen Germany
| | - Christoph Daniel
- Institute of Pathology Department of Nephropathology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Kerstin Amann
- Institute of Pathology Department of Nephropathology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Andreas L. Birkenfeld
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tuebingen Germany
- Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University Tübingen Tuebingen Germany
- German Center for Diabetes Research (DZD) at the University Tübingen Tuebingen Germany
| | - Roman Szabo
- Proteases and Tissue Remodeling Section National Institute of Dental and Craniofacial ResearchNational Institutes of Health Bethesda MD USA
| | - Thomas H. Bugge
- Proteases and Tissue Remodeling Section National Institute of Dental and Craniofacial ResearchNational Institutes of Health Bethesda MD USA
| | - Christoph Korbmacher
- Institute of Cellular and Molecular Physiology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Ferruh Artunc
- Department of Internal Medicine Division of Endocrinology, Diabetology and Nephrology University Hospital Tübingen Tuebingen Germany
- Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University Tübingen Tuebingen Germany
- German Center for Diabetes Research (DZD) at the University Tübingen Tuebingen Germany
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12
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Suzuki M, Suzuki T, Watanabe M, Hatakeyama S, Kimura S, Nakazono A, Honma A, Nakamaru Y, Vreugde S, Homma A. Role of intracellular zinc in molecular and cellular function in allergic inflammatory diseases. Allergol Int 2021; 70:190-200. [PMID: 33127267 DOI: 10.1016/j.alit.2020.09.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 09/17/2020] [Accepted: 09/22/2020] [Indexed: 12/13/2022] Open
Abstract
Zinc is an essential micronutrient in human body and a vital cofactor for the function of numerous proteins encoded by the human genome. Zinc has a critical role in maintaining many biochemical and physiological processes at the molecular, cellular, and multiple organ and systemic levels. The alteration of zinc homeostasis causes dysfunction of many organs and systems. In the immune system, zinc regulates the differentiation, proliferation and function of inflammatory cells, including T cells, eosinophils, and B cells, by modifying several signaling pathways such as NFκB signaling pathways and TCR signals. An adequate zinc level is essential for proper immune responses and decreased zinc levels were reported in many allergic inflammatory diseases, including atopic dermatitis, bronchial asthma, and chronic rhinosinusitis. Decreased zinc levels often enhance inflammatory activation. On the other hand, the inflammatory conditions alter the intracellular homeostasis of zinc, often decreasing zinc levels. These findings implied that there could be a vicious cycle between zinc deficiency and inflammatory conditions. In this review, we present recent evidence on the involvement of zinc in atopic dermatitis, bronchial asthma, and chronic rhinosinusitis, with insights into the involvement of zinc in the underlying molecular and cellular mechanisms related to these allergic inflammatory diseases.
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Affiliation(s)
- Masanobu Suzuki
- Department of Otolaryngology-Head and Neck Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido, Japan; Department of Surgery-Otorhinolaryngology Head and Neck Surgery, The Queen Elizabeth Hospital, The University of Adelaide, Australia
| | - Takayoshi Suzuki
- Department of Otolaryngology-Head and Neck Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido, Japan
| | - Masashi Watanabe
- Department of Biochemistry, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido, Japan
| | - Shigetsugu Hatakeyama
- Department of Biochemistry, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido, Japan
| | - Shogo Kimura
- Department of Otolaryngology-Head and Neck Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido, Japan
| | - Akira Nakazono
- Department of Otolaryngology-Head and Neck Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido, Japan
| | - Aya Honma
- Department of Otolaryngology-Head and Neck Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido, Japan
| | - Yuji Nakamaru
- Department of Otolaryngology-Head and Neck Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido, Japan.
| | - Sarah Vreugde
- Department of Surgery-Otorhinolaryngology Head and Neck Surgery, The Queen Elizabeth Hospital, The University of Adelaide, Australia
| | - Akihiro Homma
- Department of Otolaryngology-Head and Neck Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido, Japan
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13
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Fuentes-Prior P. Priming of SARS-CoV-2 S protein by several membrane-bound serine proteinases could explain enhanced viral infectivity and systemic COVID-19 infection. J Biol Chem 2020; 296:100135. [PMID: 33268377 PMCID: PMC7834812 DOI: 10.1074/jbc.rev120.015980] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/30/2020] [Accepted: 12/02/2020] [Indexed: 12/13/2022] Open
Abstract
The ongoing COVID-19 pandemic has already caused over a million deaths worldwide, and this death toll will be much higher before effective treatments and vaccines are available. The causative agent of the disease, the coronavirus SARS-CoV-2, shows important similarities with the previously emerged SARS-CoV-1, but also striking differences. First, SARS-CoV-2 possesses a significantly higher transmission rate and infectivity than SARS-CoV-1 and has infected in a few months over 60 million people. Moreover, COVID-19 has a systemic character, as in addition to the lungs, it also affects the heart, liver, and kidneys among other organs of the patients and causes frequent thrombotic and neurological complications. In fact, the term "viral sepsis" has been recently coined to describe the clinical observations. Here I review current structure-function information on the viral spike proteins and the membrane fusion process to provide plausible explanations for these observations. I hypothesize that several membrane-associated serine proteinases (MASPs), in synergy with or in place of TMPRSS2, contribute to activate the SARS-CoV-2 spike protein. Relative concentrations of the attachment receptor, ACE2, MASPs, their endogenous inhibitors (the Kunitz-type transmembrane inhibitors, HAI-1/SPINT1 and HAI-2/SPINT2, as well as major circulating serpins) would determine the infection rate of host cells. The exclusive or predominant expression of major MASPs in specific human organs suggests a direct role of these proteinases in e.g., heart infection and myocardial injury, liver dysfunction, kidney damage, as well as neurological complications. Thorough consideration of these factors could have a positive impact on the control of the current COVID-19 pandemic.
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Affiliation(s)
- Pablo Fuentes-Prior
- Molecular Bases of Disease, Biomedical Research Institute (IIB) Sant Pau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
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14
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Insights into the regulation of the matriptase-prostasin proteolytic system. Biochem J 2020; 477:4349-4365. [PMID: 33094801 DOI: 10.1042/bcj20200630] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/16/2020] [Accepted: 10/22/2020] [Indexed: 12/24/2022]
Abstract
The membrane-associated prostasin and matriptase belonging to the S1A subfamily of serine proteases, are critical for epithelial development and maintenance. The two proteases are involved in the activation of each other and are both regulated by the protease inhibitors, HAI-1 and HAI-2. The S1A subfamily of serine proteases are generally produced as inactive zymogens requiring a cleavage event to obtain activity. However, contrary to the common case, the zymogen form of matriptase exhibits proteolytic activity, which can be inhibited by HAI-1 and HAI-2, as for the activated counterpart. We provide strong evidence that also prostasin exhibits proteolytic activity in its zymogen form. Furthermore, we show that the activity of zymogen prostasin can be inhibited by HAI-1 and HAI-2. We report that zymogen prostasin is capable of activating zymogen matriptase, but unable to activate its own zymogen form. We propose the existence of an unusual enzyme-enzyme relationship consisting of proteolytically active zymogen forms of both matriptase and prostasin, kept under control by HAI-1 and HAI-2, and located at the pinnacle of an important proteolytic pathway in epithelia. Perturbed balance in this proteolytic system is likely to cause rapid and efficient activation of matriptase by the dual action of zymogen matriptase and zymogen prostasin. Previous studies suggest that the zymogen form of matriptase performs the normal proteolytic functions of the protease, whereas excess matriptase activation likely causes carcinogenesis. HAI-1 and HAI-2 are thus important for the prevention of matriptase activation whether catalysed by zymogen/activated prostasin (this study) or zymogen/activated matriptase (previous studies).
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15
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Murray AS, Hyland TE, Sala-Hamrick KE, Mackinder JR, Martin CE, Tanabe LM, Varela FA, List K. The cell-surface anchored serine protease TMPRSS13 promotes breast cancer progression and resistance to chemotherapy. Oncogene 2020; 39:6421-6436. [PMID: 32868877 DOI: 10.1038/s41388-020-01436-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 08/08/2020] [Accepted: 08/17/2020] [Indexed: 12/18/2022]
Abstract
Breast cancer progression is accompanied by increased expression of extracellular and cell-surface proteases capable of degrading the extracellular matrix as well as cleaving and activating downstream targets. The type II transmembrane serine proteases (TTSPs) are a family of cell-surface proteases that play critical roles in numerous types of cancers. Therefore, the aim of this study was to identify novel and uncharacterized TTSPs with differential expression in breast cancer and to determine their potential roles in progression. Systematic in silico data analysis followed by immunohistochemical validation identified increased expression of the TTSP family member, TMPRSS13 (transmembrane protease, serine 13), in invasive ductal carcinoma patient tissue samples compared to normal breast tissue. To test whether loss of TMPRSS13 impacts tumor progression, TMPRSS13 was genetically ablated in the oncogene-induced transgenic MMTV-PymT tumor model. TMPRSS13 deficiency resulted in a significant decrease in overall tumor burden and growth rate, as well as a delayed formation of detectable mammary tumors, thus suggesting a causal relationship between TMPRSS13 expression and the progression of breast cancer. Complementary studies using human breast cancer cell culture models revealed that siRNA-mediated silencing of TMPRSS13 expression decreases proliferation, induces apoptosis, and attenuates invasion. Importantly, targeting TMPRSS13 expression renders aggressive triple-negative breast cancer cell lines highly responsive to chemotherapy. At the molecular level, knockdown of TMPRSS13 in breast cancer cells led to increased protein levels of the tumor-suppressive protease prostasin. TMPRSS13/prostasin co-immunoprecipitation and prostasin zymogen activation experiments identified prostasin as a potential novel target for TMPRSS13. Regulation of prostasin levels may be a mechanism that contributes to the pro-oncogenic properties of TMPRSS13 in breast cancer. TMPRSS13 represents a novel candidate for targeted therapy in combination with standard of care chemotherapy agents in patients with hormone receptor-negative breast cancer or in patients with tumors refractory to endocrine therapy.
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Affiliation(s)
- Andrew S Murray
- Department of Pharmacology, Wayne State University, Detroit, MI, USA.,Department of Oncology, Wayne State University, Detroit, MI, USA
| | - Thomas E Hyland
- Department of Pharmacology, Wayne State University, Detroit, MI, USA
| | | | - Jacob R Mackinder
- Department of Pharmacology, Wayne State University, Detroit, MI, USA
| | - Carly E Martin
- Department of Pharmacology, Wayne State University, Detroit, MI, USA.,Department of Oncology, Wayne State University, Detroit, MI, USA
| | - Lauren M Tanabe
- Department of Pharmacology, Wayne State University, Detroit, MI, USA
| | - Fausto A Varela
- Department of Pharmacology, Wayne State University, Detroit, MI, USA
| | - Karin List
- Department of Pharmacology, Wayne State University, Detroit, MI, USA. .,Department of Oncology, Wayne State University, Detroit, MI, USA.
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16
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Wall SM, Verlander JW, Romero CA. The Renal Physiology of Pendrin-Positive Intercalated Cells. Physiol Rev 2020; 100:1119-1147. [PMID: 32347156 PMCID: PMC7474261 DOI: 10.1152/physrev.00011.2019] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 11/06/2019] [Accepted: 11/12/2019] [Indexed: 12/13/2022] Open
Abstract
Intercalated cells (ICs) are found in the connecting tubule and the collecting duct. Of the three IC subtypes identified, type B intercalated cells are one of the best characterized and known to mediate Cl- absorption and HCO3- secretion, largely through the anion exchanger pendrin. This exchanger is thought to act in tandem with the Na+-dependent Cl-/HCO3- exchanger, NDCBE, to mediate net NaCl absorption. Pendrin is stimulated by angiotensin II and aldosterone administration via the angiotensin type 1a and the mineralocorticoid receptors, respectively. It is also stimulated in models of metabolic alkalosis, such as with NaHCO3 administration. In some rodent models, pendrin-mediated HCO3- secretion modulates acid-base balance. However, of probably more physiological or clinical significance is the role of these pendrin-positive ICs in blood pressure regulation, which occurs, at least in part, through pendrin-mediated renal Cl- absorption, as well as their effect on the epithelial Na+ channel, ENaC. Aldosterone stimulates ENaC directly through principal cell mineralocorticoid hormone receptor (ligand) binding and also indirectly through its effect on pendrin expression and function. In so doing, pendrin contributes to the aldosterone pressor response. Pendrin may also modulate blood pressure in part through its action in the adrenal medulla, where it modulates the release of catecholamines, or through an indirect effect on vascular contractile force. In addition to its role in Na+ and Cl- balance, pendrin affects the balance of other ions, such as K+ and I-. This review describes how aldosterone and angiotensin II-induced signaling regulate pendrin and the contribution of pendrin-positive ICs in the kidney to distal nephron function and blood pressure.
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Affiliation(s)
- Susan M Wall
- Departments of Medicine and Physiology, Emory University School of Medicine, Atlanta, Georgia; and Department of Medicine, University of Florida, Gainesville, Florida
| | - Jill W Verlander
- Departments of Medicine and Physiology, Emory University School of Medicine, Atlanta, Georgia; and Department of Medicine, University of Florida, Gainesville, Florida
| | - Cesar A Romero
- Departments of Medicine and Physiology, Emory University School of Medicine, Atlanta, Georgia; and Department of Medicine, University of Florida, Gainesville, Florida
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17
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Zinc in Keratinocytes and Langerhans Cells: Relevance to the Epidermal Homeostasis. J Immunol Res 2018; 2018:5404093. [PMID: 30622978 PMCID: PMC6304883 DOI: 10.1155/2018/5404093] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/10/2018] [Indexed: 02/07/2023] Open
Abstract
In the skin, the epidermis is continuously exposed to various kinds of external substances and stimuli. Therefore, epidermal barriers are crucial for providing protection, safeguarding health, and regulating water balance by maintaining skin homeostasis. Disruption of the epidermal barrier allows external substances and stimuli to invade or stimulate the epidermal cells, leading to the elicitation of skin inflammation. The major components of the epidermal barrier are the stratum corneum (SC) and tight junctions (TJs). The presence of zinc in the epidermis promotes epidermal homeostasis; hence, this study reviewed the role of zinc in the formation and function of the SC and TJs. Langerhans cells (LCs) are one of the antigen-presenting cells found in the epidermis. They form TJs with adjacent keratinocytes (KCs), capture external antigens, and induce antigen-specific immune reactions. Thus, the function of zinc in LCs was examined in this review. We also summarized the general knowledge of zinc and zinc transporters in the epidermis with updated findings.
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18
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Böttcher-Friebertshäuser E, Garten W, Klenk HD. Membrane-Anchored Serine Proteases: Host Cell Factors in Proteolytic Activation of Viral Glycoproteins. ACTIVATION OF VIRUSES BY HOST PROTEASES 2018. [PMCID: PMC7122464 DOI: 10.1007/978-3-319-75474-1_8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Over one third of all known proteolytic enzymes are serine proteases. Among these, the trypsin-like serine proteases comprise one of the best characterized subfamilies due to their essential roles in blood coagulation, food digestion, fibrinolysis, or immunity. Trypsin-like serine proteases possess primary substrate specificity for basic amino acids. Most of the well-characterized trypsin-like proteases such as trypsin, plasmin, or urokinase are soluble proteases that are secreted into the extracellular environment. At the turn of the millennium, a number of novel trypsin-like serine proteases have been identified that are anchored in the cell membrane, either by a transmembrane domain at the N- or C-terminus or via a glycosylphosphatidylinositol (GPI) linkage. Meanwhile more than 20 membrane-anchored serine proteases (MASPs) have been identified in human and mouse, and some of them have emerged as key regulators of mammalian development and homeostasis. Thus, the MASP corin and TMPRSS6/matriptase-2 have been demonstrated to be the activators of the atrial natriuretic peptide (ANP) and key regulator of hepcidin expression, respectively. Furthermore, MASPs have been recognized as host cell factors activating respiratory viruses including influenza virus as well as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronaviruses. In particular, transmembrane protease serine S1 member 2 (TMPRSS2) has been shown to be essential for proteolytic activation and consequently spread and pathogenesis of a number of influenza A viruses in mice and as a factor associated with severe influenza virus infection in humans. This review gives an overview on the physiological functions of the fascinating and rapidly evolving group of MASPs and a summary of the current knowledge on their role in proteolytic activation of viral fusion proteins.
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Affiliation(s)
| | - Wolfgang Garten
- 0000 0004 1936 9756grid.10253.35Institut für Virologie, Philipps Universität, Marburg, Germany
| | - Hans Dieter Klenk
- 0000 0004 1936 9756grid.10253.35Institut für Virologie, Philipps-Universität, Marburg, Germany
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19
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Muñoz D, Serrano MK, Hernandez ME, Haller R, Swanson T, Slaton JW, Sinha AA, Wilson MJ. Matrix metalloproteinase and heparin-stimulated serine proteinase activities in post-prostate massage urine of men with prostate cancer. Exp Mol Pathol 2017; 103:300-305. [DOI: 10.1016/j.yexmp.2017.11.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 11/15/2017] [Indexed: 10/18/2022]
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20
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Shiao F, Liu LCO, Huang N, Lai YJJ, Barndt RJ, Tseng CC, Wang JK, Jia B, Johnson MD, Lin CY. Selective Inhibition of Prostasin in Human Enterocytes by the Integral Membrane Kunitz-Type Serine Protease Inhibitor HAI-2. PLoS One 2017; 12:e0170944. [PMID: 28125689 PMCID: PMC5268426 DOI: 10.1371/journal.pone.0170944] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 01/12/2017] [Indexed: 12/28/2022] Open
Abstract
Mutations of hepatocyte growth factor activator inhibitor (HAI)-2 in humans cause sodium loss in the gastrointestinal (GI) tract in patients with syndromic congenital sodium diarrhea (SCSD). Aberrant regulation of HAI-2 target protease(s) was proposed as the cause of the disease. Here functional linkage of HAI-2 with two membrane-associated serine proteases, matriptase and prostasin was analyzed in Caco-2 cells and the human GI tract. Immunodepletion-immunoblot analysis showed that significant proportion of HAI-2 is in complex with activated prostasin but not matriptase. Unexpectedly, prostasin is expressed predominantly in activated forms and was also detected in complex with HAI-1, a Kunitz inhibitor highly related to HAI-2. Immunohistochemistry showed a similar tissue distribution of prostasin and HAI-2 immunoreactivity with the most intense labeling near the brush borders of villus epithelial cells. In contrast, matriptase was detected primarily at the lateral plasma membrane, where HAI-1 was also detected. The tissue distribution profiles of immunoreactivity against these proteins, when paired with the species detected suggests that prostasin is under tight control by both HAI-1 and HAI-2 and matriptase by HAI-1 in human enterocytes. Furthermore, HAI-1 is a general inhibitor of prostasin in a variety of epithelial cells. In contrast, HAI-2 was not found to be a significant inhibitor for prostasin in mammary epithelial cells or keratinocytes. The high levels of constitutive prostasin zymogen activation and the selective prostasin inhibition by HAI-2 in enterocytes suggest that dysregulated prostasin proteolysis may be particularly important in the GI tract when HAI-2 function is lost and/or dysregulated.
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Affiliation(s)
- Frank Shiao
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University Washington DC, United States of America
| | - Li-Ching O. Liu
- College of Medicine, National Defense Medical Center, Taipei, Taiwan
| | - Nanxi Huang
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University Washington DC, United States of America
| | - Ying-Jung J. Lai
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University Washington DC, United States of America
| | - Robert J. Barndt
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University Washington DC, United States of America
| | - Chun-Che Tseng
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University Washington DC, United States of America
| | - Jehng-Kang Wang
- Department of Biochemistry, National Defense Medical Center, Taipei, Taiwan
- * E-mail: (JKW); (CYL)
| | - Bailing Jia
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University Washington DC, United States of America
- Department of Gastroenterology, Henan Provincial People’s Hospital, Zhengzhou, China
| | - Michael D. Johnson
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University Washington DC, United States of America
| | - Chen-Yong Lin
- Lombardi Comprehensive Cancer Center, Department of Oncology Georgetown University Washington DC, United States of America
- * E-mail: (JKW); (CYL)
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21
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Friis S, Madsen DH, Bugge TH. Distinct Developmental Functions of Prostasin (CAP1/PRSS8) Zymogen and Activated Prostasin. J Biol Chem 2015; 291:2577-82. [PMID: 26719335 DOI: 10.1074/jbc.c115.706721] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Indexed: 01/15/2023] Open
Abstract
The membrane-anchored serine prostasin (CAP1/PRSS8) is essential for barrier acquisition of the interfollicular epidermis and for normal hair follicle development. Consequently, prostasin null mice die shortly after birth. Prostasin is found in two forms in the epidermis: a one-chain zymogen and a two-chain proteolytically active form, generated by matriptase-dependent activation site cleavage. Here we used gene editing to generate mice expressing only activation site cleavage-resistant (zymogen-locked) endogenous prostasin. Interestingly, these mutant mice displayed normal interfollicular epidermal development and postnatal survival, but had defects in whisker and pelage hair formation. These findings identify two distinct in vivo functions of epidermal prostasin: a function in the interfollicular epidermis, not requiring activation site cleavage, that can be mediated by the zymogen-locked version of prostasin and a proteolysis-dependent function of activated prostasin in hair follicles, dependent on zymogen conversion by matriptase.
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Affiliation(s)
- Stine Friis
- From the Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland 20892, the Section for Molecular Disease Biology, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark, and
| | - Daniel H Madsen
- From the Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland 20892, the Center for Cancer Immune Therapy, Copenhagen University Hospital Herlev, DK-2730 Herlev, Denmark
| | - Thomas H Bugge
- From the Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland 20892,
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22
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The Cap1-claudin-4 regulatory pathway is important for renal chloride reabsorption and blood pressure regulation. Proc Natl Acad Sci U S A 2014; 111:E3766-74. [PMID: 25157135 DOI: 10.1073/pnas.1406741111] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The paracellular pathway through the tight junction provides an important route for transepithelial chloride reabsorption in the kidney, which regulates extracellular salt content and blood pressure. Defects in paracellular chloride reabsorption may in theory cause deregulation of blood pressure. However, there is no evidence to prove this theory or to demonstrate the in vivo role of the paracellular pathway in renal chloride handling. Here, using a tissue-specific KO approach, we have revealed a chloride transport pathway in the kidney that requires the tight junction molecule claudin-4. The collecting duct-specific claudin-4 KO animals developed hypotension, hypochloremia, and metabolic alkalosis due to profound renal wasting of chloride. The claudin-4-mediated chloride conductance can be regulated endogenously by a protease-channel-activating protease 1 (cap1). Mechanistically, cap1 regulates claudin-4 intercellular interaction and membrane stability. A putative cap1 cleavage site has been identified in the second extracellular loop of claudin-4, mutation of which abolished its regulation by cap1. The cap1 effects on paracellular chloride permeation can be extended to other proteases such as trypsin, suggesting a general mechanism may also exist for proteases to regulate the tight junction permeabilities. Together, we have discovered a theory that paracellular chloride permeability is physiologically regulated and essential to renal salt homeostasis and blood pressure control.
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23
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Lucas JM, Heinlein C, Kim T, Hernandez SA, Malik MS, True LD, Morrissey C, Corey E, Montgomery B, Mostaghel E, Clegg N, Coleman I, Brown CM, Schneider EL, Craik C, Simon JA, Bedalov A, Nelson PS. The androgen-regulated protease TMPRSS2 activates a proteolytic cascade involving components of the tumor microenvironment and promotes prostate cancer metastasis. Cancer Discov 2014; 4:1310-25. [PMID: 25122198 DOI: 10.1158/2159-8290.cd-13-1010] [Citation(s) in RCA: 356] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
UNLABELLED TMPRSS2 is an androgen-regulated cell-surface serine protease expressed predominantly in prostate epithelium. TMPRSS2 is expressed highly in localized high-grade prostate cancers and in the majority of human prostate cancer metastases. Through the generation of mouse models with a targeted deletion of Tmprss2, we demonstrate that the activity of this protease regulates cancer cell invasion and metastasis to distant organs. By screening combinatorial peptide libraries, we identified a spectrum of TMPRSS2 substrates that include pro-hepatocyte growth factor (HGF). HGF activated by TMPRSS2 promoted c-MET receptor tyrosine kinase signaling, and initiated a proinvasive epithelial-to-mesenchymal transition phenotype. Chemical library screens identified a potent bioavailable TMPRSS2 inhibitor that suppressed prostate cancer metastasis in vivo. Together, these findings provide a mechanistic link between androgen-regulated signaling programs and prostate cancer metastasis that operate via context-dependent interactions with extracellular constituents of the tumor microenvironment. SIGNIFICANCE The vast majority of prostate cancer deaths are due to metastasis. Loss of TMPRSS2 activity dramatically attenuated the metastatic phenotype through mechanisms involving the HGF-c-MET axis. Therapeutic approaches directed toward inhibiting TMPRSS2 may reduce the incidence or progression of metastasis in patients with prostate cancer.
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Affiliation(s)
- Jared M Lucas
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Cynthia Heinlein
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Tom Kim
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Susana A Hernandez
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Muzdah S Malik
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Lawrence D True
- Department of Pathology, University of Washington, Seattle, Washington
| | - Colm Morrissey
- Department of Urology, University of Washington, Seattle, Washington
| | - Eva Corey
- Department of Urology, University of Washington, Seattle, Washington
| | - Bruce Montgomery
- Department of Medicine, University of Washington, Seattle, Washington
| | - Elahe Mostaghel
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington. Department of Medicine, University of Washington, Seattle, Washington
| | - Nigel Clegg
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Ilsa Coleman
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Christopher M Brown
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California
| | - Eric L Schneider
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California
| | - Charles Craik
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California
| | - Julian A Simon
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Antonio Bedalov
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Peter S Nelson
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington. Department of Pathology, University of Washington, Seattle, Washington. Department of Urology, University of Washington, Seattle, Washington. Department of Medicine, University of Washington, Seattle, Washington.
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Friis S, Sales KU, Schafer JM, Vogel LK, Kataoka H, Bugge TH. The protease inhibitor HAI-2, but not HAI-1, regulates matriptase activation and shedding through prostasin. J Biol Chem 2014; 289:22319-32. [PMID: 24962579 DOI: 10.1074/jbc.m114.574400] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The membrane-anchored serine proteases, matriptase and prostasin, and the membrane-anchored serine protease inhibitors, hepatocyte growth factor activator inhibitor (HAI)-1 and HAI-2, are critical effectors of epithelial development and postnatal epithelial homeostasis. Matriptase and prostasin form a reciprocal zymogen activation complex that results in the formation of active matriptase and prostasin that are targets for inhibition by HAI-1 and HAI-2. Conflicting data, however, have accumulated as to the existence of auxiliary functions for both HAI-1 and HAI-2 in regulating the intracellular trafficking and activation of matriptase. In this study, we, therefore, used genetically engineered mice to determine the effect of ablation of endogenous HAI-1 and endogenous HAI-2 on endogenous matriptase expression, subcellular localization, and activation in polarized intestinal epithelial cells. Whereas ablation of HAI-1 did not affect matriptase in epithelial cells of the small or large intestine, ablation of HAI-2 resulted in the loss of matriptase from both tissues. Gene silencing studies in intestinal Caco-2 cell monolayers revealed that this loss of cell-associated matriptase was mechanistically linked to accelerated activation and shedding of the protease caused by loss of prostasin regulation by HAI-2. Taken together, these data indicate that HAI-1 regulates the activity of activated matriptase, whereas HAI-2 has an essential role in regulating prostasin-dependent matriptase zymogen activation.
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Affiliation(s)
- Stine Friis
- From the Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, and the Department of Cellular and Molecular Medicine, Faculty of Health Science, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Katiuchia Uzzun Sales
- From the Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, and Clinical Research Core, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
| | - Jeffrey Martin Schafer
- From the Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, and the College of Medicine, The Ohio State University, Columbus, Ohio 43210, and
| | - Lotte K Vogel
- the Department of Cellular and Molecular Medicine, Faculty of Health Science, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Hiroaki Kataoka
- the Section of Oncopathology and Regenerative Biology, Department of Pathology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan
| | - Thomas H Bugge
- From the Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, and
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25
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Faller N, Gautschi I, Schild L. Functional analysis of a missense mutation in the serine protease inhibitor SPINT2 associated with congenital sodium diarrhea. PLoS One 2014; 9:e94267. [PMID: 24722141 PMCID: PMC3983116 DOI: 10.1371/journal.pone.0094267] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 03/14/2014] [Indexed: 12/15/2022] Open
Abstract
Membrane-bound serine proteases play important roles in different biological processes. Their regulation by endogenous inhibitors is poorly understood. A Y163C mutation in the SPINT2 gene encoding the serine protease inhibitor Hepatocyte Growth Factor Inhibitor HAI-2 is associated with a congenital sodium diarrhea. The functional consequences of this mutation on HAI-2 activity and its physiological targets are unknown. We established a cellular assay in Xenopus laevis oocytes to study functional interactions between HAI-2 and candidate membrane-bound serine proteases expressed in the gastro-intestinal tract. We found that the wild-type form of HAI-2 is a potent inhibitor of nine gastro-intestinal serine proteases. The Y163C mutation in the second Kunitz domain of HAI-2 resulted in a complete loss of inhibitory activity on two intestinal proteases, prostasin and tmprss13. The effect of the mutation of the homologous Y68C in the first Kunitz domain of HAI-2 is consistent with a differential contribution of the two Kunitz domains of HAI-2 in the inhibition of serine proteases. By contrast to the Tyr to Cys, the Tyr to Ser substitution did not change the inhibitory potency of HAI-2, indicating that the thiol-group of the cysteine rather than the Tyr deletion is responsible for the HAI-2 loss of function. Our functional assay allowed us to identify membrane-bound serine proteases as cellular target for inhibition by HAI-2 wild type and mutants, and to better define the role of the Tyr in the second Kunitz domain in the inhibitory activity of HAI-2.
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Affiliation(s)
- Nicolas Faller
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Ivan Gautschi
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Laurent Schild
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
- * E-mail:
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The serine protease prostasin regulates hepatic insulin sensitivity by modulating TLR4 signalling. Nat Commun 2014; 5:3428. [PMID: 24614850 PMCID: PMC3959208 DOI: 10.1038/ncomms4428] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 02/10/2014] [Indexed: 01/04/2023] Open
Abstract
The effects of high-fat diet (HFD) and postprandial endotoxemia on the development of type 2 diabetes are not fully understood. Here we show that the serine protease prostasin (PRSS8) regulates hepatic insulin sensitivity by modulating Toll-like receptor 4 (TLR4)-mediated signalling. HFD triggers the suppression of PRSS8 expression by inducing endoplasmic reticulum (ER) stress and increases the TLR4 level in the liver. PRSS8 releases the ectodomain of TLR4 by cleaving it, which results in a reduction in the full-length form and reduces the activation of TLR4. Liver-specific PRSS8 knockout (LKO) mice develop insulin resistance associated with the increase in hepatic TLR4. Restoration of PRSS8 expression in livers of HFD, LKO and db/db mice decreases the TLR4 level and ameliorates insulin resistance. These results identify a novel physiological role for PRSS8 in the liver and provide new insight into the development of diabetes resulting from HFD or metabolic endotoxemia. Hepatic insulin resistance is a hallmark of diabetes, but its aetiology is incompletely understood. Here, Uchimura and colleagues show that the serine protease prostasin cleaves Toll-like receptor 4 (TLR4) and regulates hepatic insulin sensitivity by modulating TLR4-mediated signalling.
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27
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Aggarwal S, Dabla PK, Arora S. Prostasin: An Epithelial Sodium Channel Regulator. J Biomark 2013; 2013:179864. [PMID: 26317012 PMCID: PMC4436870 DOI: 10.1155/2013/179864] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 06/03/2013] [Accepted: 06/04/2013] [Indexed: 12/26/2022] Open
Abstract
Prostasin is a glycophosphatidylinositol-anchored protein which is found in prostate gland, kidney, bronchi, colon, liver, lung, pancreas, and salivary glands. It is a serine protease with trypsin-like substrate specificity which was first purified from seminal fluid in 1994. In the last decade, its diverse roles in various biological and physiological processes have been elucidated. Many studies done to date suggest that prostasin is one of several membrane peptidases regulating epithelial sodium channels in mammals. A comprehensive literature search was conducted from the websites of Pubmed Central, the US National Library of Medicine's digital archive of life sciences literature and the National Library of Medicine. The data was also assessed from journals and books that published relevant articles in this field. Understanding the mechanism by which prostasin and its inhibitors regulate sodium channels has provided a new insight into the treatment of hypertension and some other diseases like cystic fibrosis. Prostasin plays an important role in epidermal growth factor receptor (EGFR) signal modulation. Extracellular proteases have been implicated in tumor metastasis and local tissue invasion because of their ability to degrade extracellular matrices.
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Affiliation(s)
- Shakti Aggarwal
- Department of Biochemistry, ESI Hospital, Basai Darapur, New Delhi 110015, India
| | - Pradeep K. Dabla
- Department of Biochemistry, Chacha Nehru Bal Chikitsalaya, New Delhi 110031, India
| | - Sarika Arora
- Department of Biochemistry, ESI Hospital, Basai Darapur, New Delhi 110015, India
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28
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Friis S, Uzzun Sales K, Godiksen S, Peters DE, Lin CY, Vogel LK, Bugge TH. A matriptase-prostasin reciprocal zymogen activation complex with unique features: prostasin as a non-enzymatic co-factor for matriptase activation. J Biol Chem 2013; 288:19028-39. [PMID: 23673661 DOI: 10.1074/jbc.m113.469932] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Matriptase and prostasin are part of a cell surface proteolytic pathway critical for epithelial development and homeostasis. Here we have used a reconstituted cell-based system and transgenic mice to investigate the mechanistic interrelationship between the two proteases. We show that matriptase and prostasin form a reciprocal zymogen activation complex with unique features. Prostasin serves as a critical co-factor for matriptase activation. Unexpectedly, however, prostasin-induced matriptase activation requires neither prostasin zymogen conversion nor prostasin catalytic activity. Prostasin zymogen conversion to active prostasin is dependent on matriptase but does not require matriptase zymogen conversion. Consistent with these findings, wild type prostasin, activation cleavage site-mutated prostasin, and catalytically inactive prostasin all were biologically active in vivo when overexpressed in the epidermis of transgenic mice, giving rise to a severe skin phenotype. Our finding of non-enzymatic stimulation of matriptase activation by prostasin and activation of prostasin by the matriptase zymogen provides a tentative mechanistic explanation for several hitherto unaccounted for genetic and biochemical observations regarding these two membrane-anchored serine proteases and their downstream targets.
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Affiliation(s)
- Stine Friis
- Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, NIDCR, National Institutes of Health, Bethesda, Maryland 20892, USA
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29
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Szabo R, Uzzun Sales K, Kosa P, Shylo NA, Godiksen S, Hansen KK, Friis S, Gutkind JS, Vogel LK, Hummler E, Camerer E, Bugge TH. Reduced prostasin (CAP1/PRSS8) activity eliminates HAI-1 and HAI-2 deficiency-associated developmental defects by preventing matriptase activation. PLoS Genet 2012; 8:e1002937. [PMID: 22952456 PMCID: PMC3431340 DOI: 10.1371/journal.pgen.1002937] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 07/18/2012] [Indexed: 12/14/2022] Open
Abstract
Loss of either hepatocyte growth factor activator inhibitor (HAI)-1 or -2 is associated with embryonic lethality in mice, which can be rescued by the simultaneous inactivation of the membrane-anchored serine protease, matriptase, thereby demonstrating that a matriptase-dependent proteolytic pathway is a critical developmental target for both protease inhibitors. Here, we performed a genetic epistasis analysis to identify additional components of this pathway by generating mice with combined deficiency in either HAI-1 or HAI-2, along with genes encoding developmentally co-expressed candidate matriptase targets, and screening for the rescue of embryonic development. Hypomorphic mutations in Prss8, encoding the GPI-anchored serine protease, prostasin (CAP1, PRSS8), restored placentation and normal development of HAI-1–deficient embryos and prevented early embryonic lethality, mid-gestation lethality due to placental labyrinth failure, and neural tube defects in HAI-2–deficient embryos. Inactivation of genes encoding c-Met, protease-activated receptor-2 (PAR-2), or the epithelial sodium channel (ENaC) alpha subunit all failed to rescue embryonic lethality, suggesting that deregulated matriptase-prostasin activity causes developmental failure independent of aberrant c-Met and PAR-2 signaling or impaired epithelial sodium transport. Furthermore, phenotypic analysis of PAR-1 and matriptase double-deficient embryos suggests that the protease may not be critical for focal proteolytic activation of PAR-2 during neural tube closure. Paradoxically, although matriptase auto-activates and is a well-established upstream epidermal activator of prostasin, biochemical analysis of matriptase- and prostasin-deficient placental tissues revealed a requirement of prostasin for conversion of the matriptase zymogen to active matriptase, whereas prostasin zymogen activation was matriptase-independent. Vertebrate embryogenesis is dependent upon a series of precisely coordinated cell proliferation, migration, and differentiation events. Recently, the execution of these events was shown to be guided in part by extracellular cues provided by focal pericellular proteolysis by a newly identified family of membrane-anchored serine proteases. We now show that two of these membrane-anchored serine proteases, prostasin and matriptase, constitute a single proteolytic signaling cascade that is active at multiple stages of development. Furthermore, we show that failure to precisely regulate the enzymatic activity of both prostasin and matriptase by two developmentally co-expressed transmembrane serine protease inhibitors, hepatocyte growth factor activator inhibitor-1 and -2, causes an array of developmental defects, including clefting of the embryonic ectoderm, lack of placental labyrinth formation, and inability to close the neural tube. Our study also provides evidence that the failure to regulate the prostasin–matriptase cascade may derail morphogenesis independent of the activation of known protease-regulated developmental signaling pathways. Because hepatocyte growth factor activator inhibitor–deficiency in humans is known to cause an assortment of common and rare developmental abnormalities, the aberrant activity of the prostasin–matriptase cascade identified in our study may contribute importantly to genetic as well as sporadic birth defects in humans.
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Affiliation(s)
- Roman Szabo
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Katiuchia Uzzun Sales
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Peter Kosa
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Natalia A. Shylo
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Sine Godiksen
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
- Department of Cellular and Molecular Medicine, Faculty of Health Science, University of Copenhagen, Copenhagen, Denmark
- Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Karina K. Hansen
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Stine Friis
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - J. Silvio Gutkind
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Lotte K. Vogel
- Department of Cellular and Molecular Medicine, Faculty of Health Science, University of Copenhagen, Copenhagen, Denmark
| | - Edith Hummler
- Pharmacology and Toxicology Department, University de Lausanne, Lausanne, Switzerland
| | - Eric Camerer
- INSERM U970, Paris Cardiovascular Research Centre, Paris, France
- Université Paris-Descartes, Paris, France
| | - Thomas H. Bugge
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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30
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Patel AB, Chao J, Palmer LG. Tissue kallikrein activation of the epithelial Na channel. Am J Physiol Renal Physiol 2012; 303:F540-50. [PMID: 22622459 DOI: 10.1152/ajprenal.00133.2012] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Epithelial Na Channels (ENaC) are responsible for the apical entry of Na(+) in a number of different epithelia including the renal connecting tubule and cortical collecting duct. Proteolytic cleavage of γ-ENaC by serine proteases, including trypsin, furin, elastase, and prostasin, has been shown to increase channel activity. Here, we investigate the ability of another serine protease, tissue kallikrein, to regulate ENaC. We show that excretion of tissue kallikrein, which is secreted into the lumen of the connecting tubule, is stimulated following 5 days of a high-K(+) or low-Na(+) diet in rats. Urinary proteins reconstituted in a low-Na buffer activated amiloride-sensitive currents (I(Na)) in ENaC-expressing oocytes, suggesting an endogenous urinary protease can activate ENaC. We next tested whether tissue kallikrein can directly cleave and activate ENaC. When rat ENaC-expressing oocytes were exposed to purified tissue kallikrein from rat urine (RTK), ENaC currents increased threefold in both the presence and absence of a soybean trypsin inhibitor (SBTI). RTK and trypsin both decreased the apparent molecular mass of cleaved cell-surface γ-ENaC, while immunodepleted RTK produced no shift in apparent molecular mass, demonstrating the specificity of the tissue kallikrein. A decreased effect of RTK on Xenopus ENaC, which has variations in the putative prostasin cleavage sites in γ-ENaC, suggests these sites are important in RTK activation of ENaC. Mutating the prostasin site in mouse γ-ENaC (γRKRK186QQQQ) abolished ENaC activation and cleavage by RTK while wild-type mouse ENaC was activated and cleaved similar to that of the rat. We conclude that tissue kallikrein can be a physiologically relevant regulator of ENaC activity.
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Affiliation(s)
- Ankit B Patel
- Department of Physiology and Biophysics, Weill Cornell Medical College, 1300 York Ave., New York, NY 10065, USA
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31
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Nimishakavi S, Besprozvannaya M, Raymond WW, Craik CS, Gruenert DC, Caughey GH. Activity and inhibition of prostasin and matriptase on apical and basolateral surfaces of human airway epithelial cells. Am J Physiol Lung Cell Mol Physiol 2012; 303:L97-106. [PMID: 22582115 DOI: 10.1152/ajplung.00303.2011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Prostasin is a membrane-anchored protease expressed in airway epithelium, where it stimulates salt and water uptake by cleaving the epithelial Na(+) channel (ENaC). Prostasin is activated by another transmembrane tryptic protease, matriptase. Because ENaC-mediated dehydration contributes to cystic fibrosis (CF), prostasin and matriptase are potential therapeutic targets, but their catalytic competence on airway epithelial surfaces has been unclear. Seeking tools for exploring sites and modulation of activity, we used recombinant prostasin and matriptase to identify substrate t-butyloxycarbonyl-l-Gln-Ala-Arg-4-nitroanilide (QAR-4NA), which allowed direct assay of proteases in living cells. Comparisons of bronchial epithelial cells (CFBE41o-) with and without functioning cystic fibrosis transmembrane conductance regulator (CFTR) revealed similar levels of apical and basolateral aprotinin-inhibitable activity. Although recombinant matriptase was more active than prostasin in hydrolyzing QAR-4NA, cell surface activity resisted matriptase-selective inhibition, suggesting that prostasin dominates. Surface biotinylation revealed similar expression of matriptase and prostasin in epithelial cells expressing wild-type vs. ΔF508-mutated CFTR. However, the ratio of mature to inactive proprostasin suggested surface enrichment of active enzyme. Although small amounts of matriptase and prostasin were shed spontaneously, prostasin anchored to the cell surface by glycosylphosphatidylinositol was the major contributor to observed QAR-4NA-hydrolyzing activity. For example, the apical surface of wild-type CFBE41o- epithelial cells express 22% of total, extractable, aprotinin-inhibitable, QAR-4NA-hydrolyzing activity and 16% of prostasin immunoreactivity. In conclusion, prostasin is present, mature and active on the apical surface of wild-type and CF bronchial epithelial cells, where it can be targeted for inhibition via the airway lumen.
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Kota P, García-Caballero A, Dang H, Gentzsch M, Stutts MJ, Dokholyan NV. Energetic and structural basis for activation of the epithelial sodium channel by matriptase. Biochemistry 2012; 51:3460-9. [PMID: 22471557 DOI: 10.1021/bi2014773] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Limited proteolysis, accomplished by endopeptidases, is a ubiquitous phenomenon underlying the regulation and activation of many enzymes, receptors, and other proteins synthesized as inactive precursors. Serine proteases make up one of the largest and most conserved families of endopeptidases involved in diverse cellular activities, including wound healing, blood coagulation, and immune responses. Heteromeric α,β,γ-epithelial sodium channels (ENaC) associated with diseases like cystic fibrosis and Liddle's syndrome are irreversibly stimulated by membrane-anchored proteases (MAPs) and furin-like convertases. Matriptase/channel activating protease-3 (CAP3) is one of the several MAPs that potently activate ENaC. Despite identification of protease cleavage sites, the basis for the enhanced susceptibility of α- and γ-ENaC to proteases remains elusive. Here, we elucidate the energetic and structural bases for activation of ENaC by CAP3. We find a region near the γ-ENaC furin site that has previously not been identified as a critical cleavage site for CAP3-mediated stimulation. We also report that CAP3 mediates cleavage of ENaC at basic residues downstream of the furin site. Our results indicate that surface proteases alone are sufficient to fully activate uncleaved ENaC and explain how ENaC in epithelia expressing surface-active proteases can appear refractory to soluble proteases. Our results support a model in which proteases prime ENaC for activation by cleaving at the furin site, and cleavage at downstream sites is accomplished by membrane surface proteases or extracellular soluble proteases. On the basis of our results, we propose a dynamics-driven "anglerfish" mechanism that explains less stringent sequence requirements for substrate recognition and cleavage by matriptase than by furin.
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Affiliation(s)
- Pradeep Kota
- Program in Cellular and Molecular Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7260, USA
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Bergum C, Zoratti G, Boerner J, List K. Strong expression association between matriptase and its substrate prostasin in breast cancer. J Cell Physiol 2012; 227:1604-9. [PMID: 21678412 DOI: 10.1002/jcp.22877] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Breast cancer tumorigenesis is accompanied by increased levels of extracellular proteases that are capable of remodeling the extracellular matrix as well as cleaving and activating growth factors and signaling receptors that are critically involved in neoplastic progression. Multiple studies implicate the membrane anchored serine protease matriptase (also known as MT-SP1 and epithin) in breast cancer. The pro-form of the GPI-anchored serine protease prostasin has recently been identified as a physiological substrate of matriptase and the two proteases are co-expressed in multiple healthy tissues. In this study, the inter-relationship between the two membrane-anchored serine proteases in breast cancer was investigated using breast cancer cell lines and breast cancer patient samples to delineate the association between matriptase and prostasin. We used Western blotting to determine the expression of matriptase and prostasin proteins in a panel of breast cancer cell lines and immunohistochemistry to assess the expression in serial sections from breast cancer tissue arrays. We demonstrate that the expression of matriptase and prostasin is closely correlated in breast cancer cell lines as well as in breast cancer tissue samples. Furthermore, matriptase and prostasin display a near identical spatial expression pattern in the epithelial compartment of breast cancer tissue. These data suggest that the matriptase-prostasin cascade might play a critical role in breast cancer.
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Affiliation(s)
- Christopher Bergum
- Department of Pharmacology, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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The matriptase-prostasin proteolytic cascade in epithelial development and pathology. Cell Tissue Res 2012; 351:245-53. [DOI: 10.1007/s00441-012-1348-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 01/20/2012] [Indexed: 01/05/2023]
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Svenningsen P, Skøtt O, Jensen BL. Proteinuric diseases with sodium retention: is plasmin the link? Clin Exp Pharmacol Physiol 2011; 39:117-24. [DOI: 10.1111/j.1440-1681.2011.05524.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abstract
PURPOSE OF REVIEW Activation of epithelial sodium channel (ENaC) by proteolysis appears to be relevant for day-to-day physiological regulation of channel activity in kidney and other epithelial tissues. Pathophysiogical, proteolytic activation of ENaC in kidney has been demonstrated in proteinuric disease. RECENT FINDINGS A variation in sodium and potassium intake or plasma aldosterone changes the number of cleaved α and γ-ENaC subunits and is associated with changes in ENaC currents. The protease furin mediates intracellular cleavage, whereas the channel-activating protease prostasin (CAP-1), which is glycophosphatidylinositol-anchored to the apical cell surface, mediates important extracellular cleavage. Soluble protease activity is very low in urine under physiological conditions but rises in proteinuria. In nephrotic syndrome, the dominant soluble protease activity is plasmin, which is formed from filtered plasminogen via urokinase-type plasminogen activator. Plasmin activates ENaC directly at high concentrations and through prostasin at lower concentrations. SUMMARY The discovery of serine protease-mediated activation of renal ENaC in physiological and pathophysiological conditions opens the way for new understanding of the pathogenesis of proteinuric sodium retention, which may involve plasmin and present several potential new drug targets.
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Antalis TM, Bugge TH, Wu Q. Membrane-anchored serine proteases in health and disease. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 99:1-50. [PMID: 21238933 PMCID: PMC3697097 DOI: 10.1016/b978-0-12-385504-6.00001-4] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Serine proteases of the trypsin-like family have long been recognized to be critical effectors of biological processes as diverse as digestion, blood coagulation, fibrinolysis, and immunity. In recent years, a subgroup of these enzymes has been identified that are anchored directly to plasma membranes, either by a carboxy-terminal transmembrane domain (Type I), an amino-terminal transmembrane domain with a cytoplasmic extension (Type II or TTSP), or through a glycosylphosphatidylinositol (GPI) linkage. Recent biochemical, cellular, and in vivo analyses have now established that membrane-anchored serine proteases are key pericellular contributors to processes vital for development and the maintenance of homeostasis. This chapter reviews our current knowledge of the biological and physiological functions of these proteases, their molecular substrates, and their contributions to disease.
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Affiliation(s)
- Toni M Antalis
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Tervonen TA, Partanen JI, Saarikoski ST, Myllynen M, Marques E, Paasonen K, Moilanen A, Wohlfahrt G, Kovanen PE, Klefstrom J. Faulty epithelial polarity genes and cancer. Adv Cancer Res 2011; 111:97-161. [PMID: 21704831 DOI: 10.1016/b978-0-12-385524-4.00003-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Epithelial architecture is formed in tissues and organs when groups of epithelial cells are organized into polarized structures. The epithelial function and integrity as well as signaling across the epithelial layer is orchestrated by apical junctional complexes (AJCs), which are landmarks for PAR/CRUMBS and lateral SCRIB polarity modules and by dynamic interactions of the cells with underlying basement membrane (BM). These highly organized epithelial architectures are demolished in cancer. In all advanced epithelial cancers, malignant cells have lost polarity and connections to the basement membrane and they have become proliferative, motile, and invasive. Clearly, loss of epithelial integrity associates with tumor progression but does it contribute to tumor development? Evidence from studies in Drosophila and recently also in vertebrate models have suggested that even the oncogene-driven enforced cell proliferation can be conditional, dependant on the influence of cell-cell or cell-microenvironment contacts. Therefore, loss of epithelial integrity may not only be an obligate consequence of unscheduled proliferation of malignant cells but instead, malignant epithelial cells may need to acquire capacity to break free from the constraints of integrity to freely and autonomously proliferate. We discuss how epithelial polarity complexes form and regulate epithelial integrity, highlighting the roles of enzymes Rho GTPases, aPKCs, PI3K, and type II transmembrane serine proteases (TTSPs). We also discuss relevance of these pathways to cancer in light of genetic alterations found in human cancers and review molecular pathways and potential pharmacological strategies to revert or selectively eradicate disorganized tumor epithelium.
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Pech V, Pham TD, Hong S, Weinstein AM, Spencer KB, Duke BJ, Walp E, Kim YH, Sutliff RL, Bao HF, Eaton DC, Wall SM. Pendrin modulates ENaC function by changing luminal HCO3-. J Am Soc Nephrol 2010; 21:1928-41. [PMID: 20966128 DOI: 10.1681/asn.2009121257] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The epithelial Na(+) channel, ENaC, and the Cl(-)/HCO(3)(-) exchanger, pendrin, mediate NaCl absorption within the cortical collecting duct and the connecting tubule. Although pendrin and ENaC localize to different cell types, ENaC subunit abundance and activity are lower in aldosterone-treated pendrin-null mice relative to wild-type mice. Because pendrin mediates HCO(3)(-) secretion, we asked if increasing distal delivery of HCO(3)(-) through a pendrin-independent mechanism "rescues" ENaC function in pendrin-null mice. We gave aldosterone and NaHCO(3) to increase pendrin-dependent HCO(3)(-) secretion within the connecting tubule and cortical collecting duct, or gave aldosterone and NaHCO(3) plus acetazolamide to increase luminal HCO(3)(-) concentration, [HCO(3)(-)], independent of pendrin. Following treatment with aldosterone and NaHCO(3), pendrin-null mice had lower urinary pH and [HCO(3)(-)] as well as lower renal ENaC abundance and function than wild-type mice. With the addition of acetazolamide, however, acid-base balance as well as ENaC subunit abundance and function was similar in pendrin-null and wild-type mice. We explored whether [HCO(3)(-)] directly alters ENaC abundance and function in cultured mouse principal cells (mpkCCD). Amiloride-sensitive current and ENaC abundance rose with increased [HCO(3)(-)] on the apical or the basolateral side, independent of the substituting anion. However, ENaC was more sensitive to changes in [HCO(3)(-)] on the basolateral side of the monolayer. Moreover, increasing [HCO(3)(-)] on the apical and basolateral side of Xenopus kidney cells increased both ENaC channel density and channel activity. We conclude that pendrin modulates ENaC abundance and function, at least in part by increasing luminal [HCO(3)(-)] and/or pH.
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Affiliation(s)
- Vladimir Pech
- Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
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40
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The cutting edge: membrane-anchored serine protease activities in the pericellular microenvironment. Biochem J 2010; 428:325-46. [PMID: 20507279 DOI: 10.1042/bj20100046] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The serine proteases of the trypsin-like (S1) family play critical roles in many key biological processes including digestion, blood coagulation, and immunity. Members of this family contain N- or C-terminal domains that serve to tether the serine protease catalytic domain directly to the plasma membrane. These membrane-anchored serine proteases are proving to be key components of the cell machinery for activation of precursor molecules in the pericellular microenvironment, playing vital functions in the maintenance of homoeostasis. Substrates activated by membrane-anchored serine proteases include peptide hormones, growth and differentiation factors, receptors, enzymes, adhesion molecules and viral coat proteins. In addition, new insights into our understanding of the physiological functions of these proteases and their involvement in human pathology have come from animal models and patient studies. The present review discusses emerging evidence for the diversity of this fascinating group of membrane serine proteases as potent modifiers of the pericellular microenvironment through proteolytic processing of diverse substrates. We also discuss the functional consequences of the activities of these proteases on mammalian physiology and disease.
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Clark EB, Jovov B, Rooj AK, Fuller CM, Benos DJ. Proteolytic cleavage of human acid-sensing ion channel 1 by the serine protease matriptase. J Biol Chem 2010; 285:27130-27143. [PMID: 20601429 DOI: 10.1074/jbc.m110.153213] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Acid-sensing ion channel 1 (ASIC1) is a H(+)-gated channel of the amiloride-sensitive epithelial Na(+) channel (ENaC)/degenerin family. ASIC1 is expressed mostly in the central and peripheral nervous system neurons. ENaC and ASIC function is regulated by several serine proteases. The type II transmembrane serine protease matriptase activates the prototypical alphabetagammaENaC channel, but we found that matriptase is expressed in glioma cells and its expression is higher in glioma compared with normal astrocytes. Therefore, the goal of this study was to test the hypothesis that matriptase regulates ASIC1 function. Matriptase decreased the acid-activated ASIC1 current as measured by two-electrode voltage clamp in Xenopus oocytes and cleaved ASIC1 expressed in oocytes or CHO K1 cells. Inactive S805A matriptase had no effect on either the current or the cleavage of ASIC1. The effect of matriptase on ASIC1 was specific, because it did not affect the function of ASIC2 and no matriptase-specific ASIC2 fragments were detected in oocytes or in CHO cells. Three matriptase recognition sites were identified in ASIC1 (Arg-145, Lys-185, and Lys-384). Site-directed mutagenesis of these sites prevented matriptase cleavage of ASIC1. Our results show that matriptase is expressed in glioma cells and that matriptase specifically cleaves ASIC1 in heterologous expression systems.
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Affiliation(s)
- Edlira B Clark
- Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Biljana Jovov
- Department of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Arun K Rooj
- Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Catherine M Fuller
- Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Dale J Benos
- Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, Alabama 35294.
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Spraggon G, Hornsby M, Shipway A, Tully DC, Bursulaya B, Danahay H, Harris JL, Lesley SA. Active site conformational changes of prostasin provide a new mechanism of protease regulation by divalent cations. Protein Sci 2009; 18:1081-1094. [PMID: 19388054 PMCID: PMC2771310 DOI: 10.1002/pro.118] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Revised: 02/26/2009] [Accepted: 02/27/2009] [Indexed: 01/28/2025]
Abstract
Prostasin or human channel-activating protease 1 has been reported to play a critical role in the regulation of extracellular sodium ion transport via its activation of the epithelial cell sodium channel. Here, the structure of the extracellular portion of the membrane associated serine protease has been solved to high resolution in complex with a nonselective d-FFR chloromethyl ketone inhibitor, in an apo form, in a form where the apo crystal has been soaked with the covalent inhibitor camostat and in complex with the protein inhibitor aprotinin. It was also crystallized in the presence of the divalent cation Ca(+2). Comparison of the structures with each other and with other members of the trypsin-like serine protease family reveals unique structural features of prostasin and a large degree of conformational variation within specificity determining loops. Of particular interest is the S1 subsite loop which opens and closes in response to basic residues or divalent ions, directly binding Ca(+2) cations. This induced fit active site provides a new possible mode of regulation of trypsin-like proteases adapted in particular to extracellular regions with variable ionic concentrations such as the outer membrane layer of the epithelial cell.
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Affiliation(s)
- Glen Spraggon
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, USA.
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43
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Coote K, Atherton-Watson HC, Sugar R, Young A, MacKenzie-Beevor A, Gosling M, Bhalay G, Bloomfield G, Dunstan A, Bridges RJ, Sabater JR, Abraham WM, Tully D, Pacoma R, Schumacher A, Harris J, Danahay H. Camostat attenuates airway epithelial sodium channel function in vivo through the inhibition of a channel-activating protease. J Pharmacol Exp Ther 2009; 329:764-74. [PMID: 19190233 DOI: 10.1124/jpet.108.148155] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2025] Open
Abstract
Inhibition of airway epithelial sodium channel (ENaC) function enhances mucociliary clearance (MCC). ENaC is positively regulated by channel-activating proteases (CAPs), and CAP inhibitors are therefore predicted to be beneficial in diseases associated with impaired MCC. The aims of the present study were to 1) identify low-molecular-weight inhibitors of airway CAPs and 2) to establish whether such CAP inhibitors would translate into a negative regulation of ENaC function in vivo, with a consequent enhancement of MCC. To this end, camostat, a trypsin-like protease inhibitor, provided a potent (IC(50) approximately 50 nM) and prolonged attenuation of ENaC function in human airway epithelial cell models that was reversible upon the addition of excess trypsin. In primary human bronchial epithelial cells, a potency order of placental bikunin > camostat > 4-guanidinobenzoic acid 4-carboxymethyl-phenyl ester > aprotinin >> soybean trypsin inhibitor = alpha1-antitrypsin, was largely consistent with that observed for inhibition of prostasin, a molecular candidate for the airway CAP. In vivo, topical airway administration of camostat induced a potent and prolonged attenuation of ENaC activity in the guinea pig trachea (ED(50) = 3 microg/kg). When administered by aerosol inhalation in conscious sheep, camostat enhanced MCC out to at least 5 h after inhaled dosing. In summary, camostat attenuates ENaC function and enhances MCC, providing an opportunity for this approach toward the negative regulation of ENaC function to be tested therapeutically.
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Affiliation(s)
- K Coote
- Novartis Institutes for Biomedical Research, Horsham, West Sussex, UK
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Abstract
Pericellular proteases can degrade extracellular matrix proteins and reshape their microenvironment, as well as cleave and activate signaling molecules such as growth factors and their receptors. In this capacity, pericellular proteolysis is essential for multiple biological processes, including development, tissue homeostasis and tissue repair. On the flip side, dysregulated pericellular proteolysis is a hallmark in many pathological conditions including cancer, and is believed to be critically involved in tumor growth, invasion and dissemination of cancer cells to other organs. Matriptase is a member of the family of Type II transmembrane serine proteases, and has been implicated in a variety of epithelial cancers. This review summarizes current knowledge about matriptase and its role in cancer based on expression studies, biochemical characterization, cell-culture based studies and in vivo experiments.
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Affiliation(s)
- Karin List
- Department of Pharmacology, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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45
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Kleyman TR, Carattino MD, Hughey RP. ENaC at the cutting edge: regulation of epithelial sodium channels by proteases. J Biol Chem 2009; 284:20447-51. [PMID: 19401469 DOI: 10.1074/jbc.r800083200] [Citation(s) in RCA: 229] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Epithelial Na+ channels facilitate the transport of Na+ across high resistance epithelia. Proteolytic cleavage has an important role in regulating the activity of these channels by increasing their open probability. Specific proteases have been shown to activate epithelial Na+ channels by cleaving channel subunits at defined sites within their extracellular domains. This minireview addresses the mechanisms by which proteases activate this channel and the question of why proteolysis has evolved as a mechanism of channel activation.
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Affiliation(s)
- Thomas R Kleyman
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA
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46
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Neth P, Profanter B, Geissler C, Nägler DK, Nerlich A, Sommerhoff CP, Jochum M. T-SP1: a novel serine protease-like protein predominantly expressed in testis. Biol Chem 2009; 389:1495-504. [PMID: 18844450 DOI: 10.1515/bc.2008.170] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Here, we describe a novel member in the group of membrane-anchored chymotrypsin (S1)-like serine proteases, namely testis serine protease 1 (T-SP1), as it is principally expressed in testis tissue. The human T-SP1 gene encompasses 28.7 kb on the short arm of chromosome 8 and consists of seven exons. Rapid amplification of cDNA ends (RACE) experiments revealed that due to alternative splicing three different variants (T-SP1/1, -2, -3) are detectable in testis tissue displaying pronounced heterogeneity at their 3'-end. T-SP1/1 consists of an 18 amino acid signal peptide and of a 49 amino acid propeptide. The following domain with the catalytic triad of His(108), Asp(156), and Ser(250) shares sequence identities of 42% and 40% with the blood coagulation factor XI and plasma kallikrein, respectively. Only T-SP1/1 contains a hydrophobic part at the C-terminus, which provides the basis for cell membrane anchoring. Using a newly generated polyclonal anti-T-SP1 antibody, expression of the T-SP1 protein was found in the Leydig and Sertoli cells of the testis and in the epithelial cells of the ductuli efferentes. Notably, T-SP1 protein was also detectable in prostate cancer and in some ovarian cancer tissues, indicating tumor-related synthesis of T-SP1 beyond testis tissue.
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Affiliation(s)
- Peter Neth
- Division of Clinical Chemistry and Clinical Biochemistry, Department of Surgery, Ludwig Maximilians University, D-80336 Munich, Germany.
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47
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Tully DC, Vidal A, Chatterjee AK, Williams JA, Roberts MJ, Petrassi HM, Spraggon G, Bursulaya B, Pacoma R, Shipway A, Schumacher AM, Danahay H, Harris JL. Discovery of inhibitors of the channel-activating protease prostasin (CAP1/PRSS8) utilizing structure-based design. Bioorg Med Chem Lett 2008; 18:5895-9. [DOI: 10.1016/j.bmcl.2008.08.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 08/08/2008] [Accepted: 08/11/2008] [Indexed: 11/15/2022]
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48
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Rickert KW, Kelley P, Byrne NJ, Diehl RE, Hall DL, Montalvo AM, Reid JC, Shipman JM, Thomas BW, Munshi SK, Darke PL, Su HP. Structure of human prostasin, a target for the regulation of hypertension. J Biol Chem 2008; 283:34864-72. [PMID: 18922802 DOI: 10.1074/jbc.m805262200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Prostasin (also called channel activating protease-1 (CAP1)) is an extracellular serine protease implicated in the modulation of fluid and electrolyte regulation via proteolysis of the epithelial sodium channel. Several disease states, particularly hypertension, can be affected by modulation of epithelial sodium channel activity. Thus, understanding the biochemical function of prostasin and developing specific agents to inhibit its activity could have a significant impact on a widespread disease. We report the expression of the prostasin proenzyme in Escherichia coli as insoluble inclusion bodies, refolding and activating via proteolytic removal of the N-terminal propeptide. The refolded and activated enzyme was shown to be pure and monomeric, with kinetic characteristics very similar to prostasin expressed from eukaryotic systems. Active prostasin was crystallized, and the structure was determined to 1.45 A resolution. These apoprotein crystals were soaked with nafamostat, allowing the structure of the inhibited acyl-enzyme intermediate structure to be determined to 2.0 A resolution. Comparison of the inhibited and apoprotein forms of prostasin suggest a mechanism of regulation through stabilization of a loop which interferes with substrate recognition.
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Affiliation(s)
- Keith W Rickert
- Department of Global Structural Biology, Merck Research Laboratories, West Point, Pennsylvania 19486, USA.
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García-Caballero A, Dang Y, He H, Stutts MJ. ENaC Proteolytic Regulation by Channel-activating Protease 2. J Gen Physiol 2008; 132:521-35. [PMID: 18852303 PMCID: PMC2571966 DOI: 10.1085/jgp.200810030] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Epithelial sodium channels (ENaCs) perform diverse physiological roles by mediating Na+ absorption across epithelial surfaces throughout the body. Excessive Na+ absorption in kidney and colon elevates blood pressure and in the airways disrupts mucociliary clearance. Potential therapies for disorders of Na+ absorption require better understanding of ENaC regulation. Recent work has established partial and selective proteolysis of ENaCs as an important means of channel activation. In particular, channel-activating transmembrane serine proteases (CAPs) and cognate inhibitors may be important in tissue-specific regulation of ENaCs. Although CAP2 (TMPRSS4) requires catalytic activity to activate ENaCs, there is not yet evidence of ENaC fragments produced by this serine protease and/or identification of the site(s) where CAP2 cleaves ENaCs. Here, we report that CAP2 cleaves at multiple sites in all three ENaC subunits, including cleavage at a conserved basic residue located in the vicinity of the degenerin site (α-K561, β-R503, and γ-R515). Sites in α-ENaC at K149/R164/K169/R177 and furin-consensus sites in α-ENaC (R205/R231) and γ-ENaC (R138) are responsible for ENaC fragments observed in oocytes coexpressing CAP2. However, the only one of these demonstrated cleavage events that is relevant for the channel activation by CAP2 takes place in γ-ENaC at position R138, the previously identified furin-consensus cleavage site. Replacement of arginine by alanine or glutamine (α,β,γR138A/Q) completely abolished both the Na+ current (INa) and a 75-kD γ-ENaC fragment at the cell surface stimulated by CAP2. Replacement of γ-ENaC R138 with a conserved basic residue, lysine, preserved both the CAP2-induced INa and the 75-kD γ-ENaC fragment. These data strongly support a model where CAP2 activates ENaCs by cleaving at R138 in γ-ENaC.
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Affiliation(s)
- Agustín García-Caballero
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina, Chapel Hill, NC 27599
| | - Yan Dang
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina, Chapel Hill, NC 27599
| | - Hong He
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina, Chapel Hill, NC 27599
| | - M. Jackson Stutts
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina, Chapel Hill, NC 27599
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50
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Diakov A, Bera K, Mokrushina M, Krueger B, Korbmacher C. Cleavage in the {gamma}-subunit of the epithelial sodium channel (ENaC) plays an important role in the proteolytic activation of near-silent channels. J Physiol 2008; 586:4587-608. [PMID: 18669538 DOI: 10.1113/jphysiol.2008.154435] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The mechanisms by which proteases activate the epithelial sodium channel (ENaC) are not yet fully understood. We investigated the effect of extracellular proteases on rat ENaC heterologously expressed in Xenopus laevis oocytes. Application of trypsin increased ENaC whole-oocyte currents by about 8-fold without a concomitant increase in channel surface expression. The stimulatory effect of trypsin was preserved in oocytes expressing alphagamma-ENaC, but was abolished in oocytes expressing alphabeta-ENaC. Thus, the gamma-subunit appears to be essential for channel activation by extracellular proteases. Site-directed mutagenesis of a putative prostasin cleavage site in the extracellular loop of the gamma-subunit revealed that mutating the 181Lys residue to alanine (gammaK181A) increases ENaC baseline whole-oocyte currents, decreases channel surface expression, and largely reduces the stimulatory effect of extracellular proteases (trypsin, chymotrypsin and human neutrophil elastase). In single-channel recordings from outside-out patches we demonstrated that the gammaK181A mutation essentially abolishes the activation of near-silent channels by trypsin, while a stimulatory effect of trypsin on channel gating is preserved. This apparent dual effect of trypsin on channel gating and on the recruitment of near-silent channels was confirmed by experiments using the beta518C mutant ENaC which can be converted to a channel with an open probability of nearly one by exposure to a sulfhydryl reagent. Interestingly, the gammaK181A mutation results in the spontaneous appearance of a 67 kDa fragment of the gamma-subunit in the plasma membrane which can be prevented by a furin inhibitor and also occurs after channel activation by extracellular trypsin. This suggests that the mutation promotes channel cleavage and activation by endogenous proteases. This would lower the pool of near-silent channels and explain the constitutive activation and reduced responsiveness of the mutant channel to extracellular proteases. We conclude that the mutated site (K181A) affects a region in the gamma-subunit of ENaC that is functionally important for the activation of near-silent channels by extracellular proteases.
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Affiliation(s)
- Alexei Diakov
- Institut für Zelluläre und Molekulare Physiologie, Waldstr 6, 91054 Erlangen, Germany.
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